/**
 * 
 */

(function($) {

// static constructs
$.tools = $.tools || {version: '@VERSION'};

$.tools.scrollable = {

conf: {
activeClass: 'active',
circular: false,
clonedClass: 'cloned',
disabledClass: 'disabled',
easing: 'swing',
initialIndex: 0,
item: '.kocka2',
items: '.items',
keyboard: true,
mousewheel: false,
next: '.next',
prev: '.prev',
size: 1,
speed: 400,
vertical: false,
touch: true,
wheelSpeed: 0
}
};

// get hidden element's width or height even though it's hidden
function dim(el, key) {
var v = parseInt(el.css(key), 10);
if (v) { return v; }
var s = el[0].currentStyle;
return s && s.width && parseInt(s.width, 10);
}

function find(root, query) {
var el = $(query);
return el.length < 2 ? el : root.parent().find(query);
}

var current;

// constructor
function Scrollable(root, conf) {

// current instance
var self = this,
fire = root.add(self),
itemWrap = root.children(),
index = 0,
vertical = conf.vertical;

if (!current) { current = self; }
if (itemWrap.length > 1) { itemWrap = $(conf.items, root); }


// in this version circular not supported when size > 1
if (conf.size > 1) { conf.circular = false; }

// methods
$.extend(self, {

getConf: function() {
return conf;
},

getIndex: function() {
return index;
},

getSize: function() {
return self.getItems().size();
},

getNaviButtons: function() {
return prev.add(next);
},

getRoot: function() {
return root;
},

getItemWrap: function() {
return itemWrap;
},

getItems: function() {
return itemWrap.find(conf.item).not("." + conf.clonedClass);
},

move: function(offset, time) {
return self.seekTo(index + offset, time);
},

next: function(time) {
return self.move(conf.size, time);
},

prev: function(time) {
return self.move(-conf.size, time);
},

begin: function(time) {
return self.seekTo(0, time);
},

end: function(time) {
return self.seekTo(self.getSize() -1, time);
},

focus: function() {
current = self;
return self;
},

addItem: function(item) {
item = $(item);

if (!conf.circular) {
itemWrap.append(item);
next.removeClass("disabled");

} else {
itemWrap.children().last().before(item);
itemWrap.children().first().replaceWith(item.clone().addClass(conf.clonedClass));
}

fire.trigger("onAddItem", [item]);
return self;
},


/* all seeking functions depend on this */
seekTo: function(i, time, fn) {

// ensure numeric index
if (!i.jquery) { i *= 1; }

// avoid seeking from end clone to the beginning
if (conf.circular && i === 0 && index == -1 && time !== 0) { return self; }

// check that index is sane
if (!conf.circular && i < 0 || i > self.getSize() || i < -1) { return self; }

var item = i;

if (i.jquery) {
i = self.getItems().index(i);

} else {
item = self.getItems().eq(i);
}

// onBeforeSeek
var e = $.Event("onBeforeSeek");
if (!fn) {
fire.trigger(e, [i, time]);
if (e.isDefaultPrevented() || !item.length) { return self; }
}

var props = vertical ? {top: -item.position().top} : {left: -item.position().left};


index = i;
current = self;
if (time === undefined) { time = conf.speed; }

itemWrap.animate(props, time, conf.easing, fn || function() {
fire.trigger("onSeek", [i]);
});

return self;
}

});

// callbacks
$.each(['onBeforeSeek', 'onSeek', 'onAddItem'], function(i, name) {

// configuration
if ($.isFunction(conf[name])) {
$(self).bind(name, conf[name]);
}

self[name] = function(fn) {
if (fn) { $(self).bind(name, fn); }
return self;
};
});

// circular loop
if (conf.circular) {

var cloned1 = self.getItems().slice(-1).clone().prependTo(itemWrap),
cloned2 = self.getItems().eq(1).clone().appendTo(itemWrap);

cloned1.add(cloned2).addClass(conf.clonedClass);

self.onBeforeSeek(function(e, i, time) {

if (e.isDefaultPrevented()) { return; }

/*
1. animate to the clone without event triggering
2. seek to correct position with 0 speed
*/
if (i == -1) {
self.seekTo(cloned1, time, function() {
self.end(0);
});
return e.preventDefault();

} else if (i == self.getSize()) {
self.seekTo(cloned2, time, function() {
self.begin(0);
});
}

});

// seek over the cloned item

// if the scrollable is hidden the calculations for seekTo position
// will be incorrect (eg, if the scrollable is inside an overlay).
// ensure the elements are shown, calculate the correct position,
// then re-hide the elements. This must be done synchronously to
// prevent the hidden elements being shown to the user.

// See: https://github.com/jquerytools/jquerytools/issues#issue/87

var hidden_parents = root.parents().add(root).filter(function () {
if ($(this).css('display') === 'none') {
return true;
}
});
if (hidden_parents.length) {
hidden_parents.show();
self.seekTo(0, 0, function() {});
hidden_parents.hide();
}
else {
self.seekTo(0, 0, function() {});
}

}

// next/prev buttons
var prev = find(root, conf.prev).click(function(e) { e.stopPropagation(); self.prev(); }),
next = find(root, conf.next).click(function(e) { e.stopPropagation(); self.next(); });

if (!conf.circular) {
self.onBeforeSeek(function(e, i) {
setTimeout(function() {
if (!e.isDefaultPrevented()) {
prev.toggleClass(conf.disabledClass, i <= 0);
next.toggleClass(conf.disabledClass, i >= self.getSize() -1);
}
}, 1);
});

if (!conf.initialIndex) {
prev.addClass(conf.disabledClass);
}
}

if (self.getSize() < 2) {
prev.add(next).addClass(conf.disabledClass);
}

// mousewheel support
if (conf.mousewheel && $.fn.mousewheel) {
root.mousewheel(function(e, delta) {
if (conf.mousewheel) {
self.move(delta < 0 ? 1 : -1, conf.wheelSpeed || 50);
return false;
}
});
}

// touch event
if (conf.touch) {
var touch = {};

itemWrap[0].ontouchstart = function(e) {
var t = e.touches[0];
touch.x = t.clientX;
touch.y = t.clientY;
};

itemWrap[0].ontouchmove = function(e) {

// only deal with one finger
if (e.touches.length == 1 && !itemWrap.is(":animated")) {
var t = e.touches[0],
deltaX = touch.x - t.clientX,
deltaY = touch.y - t.clientY;

self[vertical && deltaY > 0 || !vertical && deltaX > 0 ? 'next' : 'prev']();
e.preventDefault();
}
};
}

if (conf.keyboard) {

$(document).bind("keydown.scroll", function(evt) {

// skip certain conditions
if (!conf.keyboard || evt.altKey || evt.ctrlKey || evt.metaKey || $(evt.target).is(":input")) {
return;
}

// does this instance have focus?
if (conf.keyboard != 'static' && current != self) { return; }

var key = evt.keyCode;

if (vertical && (key == 38 || key == 40)) {
self.move(key == 38 ? -1 : 1);
return evt.preventDefault();
}

if (!vertical && (key == 37 || key == 39)) {
self.move(key == 37 ? -1 : 1);
return evt.preventDefault();
}

});
}

// initial index
if (conf.initialIndex) {
self.seekTo(conf.initialIndex, 0, function() {});
}
}


// jQuery plugin implementation
$.fn.scrollable = function(conf) {

// already constructed --> return API
var el = this.data("scroll");
if (el) { return el; }

conf = $.extend({}, $.tools.scrollable.conf, conf);

this.each(function() {
el = new Scrollable($(this), conf);
$(this).data("scroll", el);
});

return conf.api ? el: this;

};


})(jQuery);